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DTC C0049:7C [ELECTRONICALLY CONTROLLED BRAKE UNIT]

id0402c6017800

Outline

System malfunction location

Brake fluid leakage or trapped air

Detection condition

•  The electronically controlled brake unit detects brake fluid leakage.

Fail-safe

Refer to “DTC Table” and “Fail-safe Function Malfunction Contents Table”. (See DTC TABLE [ELECTRONICALLY CONTROLLED BRAKE UNIT].)

Possible cause

•  Trapped air

•  Electronically controlled brake unit malfunction

―  Brake fluid leakage

System wiring diagram

Not applicable

Connector diagram

Not applicable

System malfunction location	Brake fluid leakage or trapped air
Detection condition	• The electronically controlled brake unit detects brake fluid leakage.
Fail-safe	Refer to “DTC Table” and “Fail-safe Function Malfunction Contents Table”. (See DTC TABLE [ELECTRONICALLY CONTROLLED BRAKE UNIT].)
Possible cause	• Trapped air • Electronically controlled brake unit malfunction ― Brake fluid leakage
System wiring diagram	Not applicable
Connector diagram	Not applicable

Diagnostic Procedure

Step

Inspection

Results

Action

1

VERIFY IF AIR IS TRAPPED IN BRAKE LINE

•  Bleed the air from brake fluid.

•  Clear the DTC recorded in the memory.
(See CLEARING DTC.)

•  Perform the work of depressing the brake pedal for 3 s or more and then releasing it for 5 times or more with the ignition switched ON (engine off or on).

•  Drive the vehicle at a speed exceeding 50 km/h {31 mph}.

•  Gradually slow down and stop vehicle.

•  Perform the DTC inspection for the electronically controlled brake unit.
(See DTC INSPECTION.)

•  Is the same Pending DTC present?

Yes

Go to the next step.

No

Go to repair completion verification 2.

Repair completion verification 1

VERIFY THAT VEHICLE IS REPAIRED

•  Clear the DTC recorded in the memory.
(See CLEARING DTC.)

•  Perform the work of depressing the brake pedal for 3 s or more and then releasing it for 5 times or more with the ignition switched ON (engine off or on).

•  Drive the vehicle at a speed exceeding 50 km/h {31 mph}.

•  Gradually slow down and stop vehicle.

•  Perform the DTC inspection for the electronically controlled brake unit.
(See DTC INSPECTION.)

•  Is the same Pending DTC present?

Yes

Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error.

(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].)

If the CAN communication is normal, perform the diagnosis from Step 1.

•  If the malfunction recurs, replace the electronically controlled brake unit, then go to the next step.
(See ELECTRONICALLY CONTROLLED BRAKE UNIT REMOVAL/INSTALLATION [L.H.D.].)

(See ELECTRONICALLY CONTROLLED BRAKE UNIT REMOVAL/INSTALLATION [R.H.D.].)

No

Go to the next step.

Repair completion verification 2

VERIFY IF OTHER DTCs DISPLAYED

•  Perform the DTC inspection.
(See DTC INSPECTION.)

•  Are any DTCs displayed?

Yes

Repair the malfunctioning location according to the applicable DTC troubleshooting.

No

DTC troubleshooting completed.

Step	Inspection	Results	Action
1	VERIFY IF AIR IS TRAPPED IN BRAKE LINE • Bleed the air from brake fluid. • Clear the DTC recorded in the memory. (See CLEARING DTC.) • Perform the work of depressing the brake pedal for 3 s or more and then releasing it for 5 times or more with the ignition switched ON (engine off or on). • Drive the vehicle at a speed exceeding 50 km/h {31 mph}. • Gradually slow down and stop vehicle. • Perform the DTC inspection for the electronically controlled brake unit. (See DTC INSPECTION.) • Is the same Pending DTC present?	Yes	Go to the next step.
1		No	Go to repair completion verification 2.
Repair completion verification 1	VERIFY THAT VEHICLE IS REPAIRED • Clear the DTC recorded in the memory. (See CLEARING DTC.) • Perform the work of depressing the brake pedal for 3 s or more and then releasing it for 5 times or more with the ignition switched ON (engine off or on). • Drive the vehicle at a speed exceeding 50 km/h {31 mph}. • Gradually slow down and stop vehicle. • Perform the DTC inspection for the electronically controlled brake unit. (See DTC INSPECTION.) • Is the same Pending DTC present?	Yes	Refer to the controller area network (CAN) malfunction diagnosis flow to inspect for a CAN communication error. (See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].) If the CAN communication is normal, perform the diagnosis from Step 1. • If the malfunction recurs, replace the electronically controlled brake unit, then go to the next step. (See ELECTRONICALLY CONTROLLED BRAKE UNIT REMOVAL/INSTALLATION [L.H.D.].) (See ELECTRONICALLY CONTROLLED BRAKE UNIT REMOVAL/INSTALLATION [R.H.D.].)
Repair completion verification 1		No	Go to the next step.
Repair completion verification 2	VERIFY IF OTHER DTCs DISPLAYED • Perform the DTC inspection. (See DTC INSPECTION.) • Are any DTCs displayed?	Yes	Repair the malfunctioning location according to the applicable DTC troubleshooting.
Repair completion verification 2		No	DTC troubleshooting completed.